Pilot light



Oct. 1,1935.

A. s'rocKsTRoM ET AL 2,015,766

PILOT LIGHT Filed Dec. 30, 1952 gr wms 0Q swam Patented Oct. 1 1935 PATENT OFFICE PILOT LIGHT Arthur Stockstrom and John Gerald Kosky, St.

Louis, Mo., assignors to American Stove Company, St. Louis, Mo.,

Jersey a corporation of New Application December 30, 1932, Serial No. 649,618

3 Claims.

This invention relates to improvements in pilot lights and pertains more particularly to the pilot light fuel control valve for a pilot light of the constant burning type suitable for and commonly {S -used in connection with automatic lighters for gas ranges.

The primary object of the invention is the provision of a new and improved pilot light having a new and improved pilot light fuel control valve zconstructed in a novel and distinctive manner to prevent clogging of. the valve.

Other specific objects, novel features of construction and improved results of the invention will appear in more detail in the following de- 151: scription when read in the light of the accompanying drawing.

In the drawing: a

Figure 1 is a. top plan view of the improved pilot light and valve.

202%. Fig. 2 is a vertical sectional view of the im-,

proved pilot light and valve.

- The present improved pilot light and fuel control valve therefor has been designed particularly as a constant burning pilot light for use in con- 252 nection with automatic lighters for gas ranges.

There are many types and constructions of automatic lighters used in connection with gas ranges and. as an example of a construction in which the present pilot light is applicable for use, 30g=attention is directed to the Patent No. 1,957,442 in the name of Isaac Vernon Brumbaugh, Douglas D. Burnside and Lester S. Kauffman, entitled Flash lighter construction for gas range. The automatic lighter illustrated in the above iden- 35'=.=.tified patent requires a constant burning pilot light and since the introduction to the trade of this automatic lighter for gas ranges constant diificulty and trouble has been experienced by reason of the pilot light fuel adjustment valve ion-becoming clogged which causes a reduction in the amount of fuel delivery to the constant burning pilot which in turn consequently reduces the size of the flame of the constant burning pilot light to a point so low that the automatic lighter 45;ifinally becomes inoperative due to the failure of the constant burning pilot light to properly function.

A very considerable amount of research and development work discloses that there are pri- 60 marily three main causes for the clogging of the fuel control valves of constantly burning pilot lights. The first of these causes is that foreign matter is in suspension in the gas delivered to the pilot light. This foreign matter has been 55 found to be dust, iron oxide and particles of pipe thefuel control valves of the pilot lights, is found 10 l in respect to manufactured gas and results in a deposit in the valve parts of what we have termed These gums are hydrocarbon compounds of which comparatively little is known.

They are present in most manufactured gases and l are difficult to remove from the gases economically. These compounds are found to cause a deposit on the valve parts which reduces the fuel opening through and past the valve which causes a reduction of fuel delivered to the pilot light and a consequent reduction in flame size at the light. This deposit on the valve parts takes place rapidly and in a very short time the pilot flame has been reduced in size to such an. extent that the automatic lighter equipment becomes inoperative.

The first and second causes recited which result in the clogging of the fuel control valves of pilot lights can be removed by the proper cleaning of the gas, but the deposit of gums will almostinvariably take place as the hydrocarbon compounds are rarely if ever removed from manufactured gas due to the difliculty and the expense involved in thoroughly purifying and cleaning this manufactured gas.

Having discovered the causes of the clogging of the fuel control valves of constant burning pilot lights, the present improved invention has been conceived for overcoming and removing the difiiculties heretofore enumerated.

Having reference now to the drawing which illustrates the newly developed improved construction, A indicates a valve fitting or body to which gas is delivered from the main gas manifold (not shown) by a supply pipe B, the upper end of which is threadedly engaged as at 3 in the enlarged end 4 of a plug C which has therein a fuel passageway 5. The plug C has a reduced end 6 which threadedly engages as at l the lower face or under side of the valve body A so that its passageway 5 communicates with the chamber 8 in the valve body. In its top or upper face 9 the valve body is provided with an outwardly extending exteriorly threaded gas outlet I!) the lower end of which communicates with a gas passageway II which passageway in 56 turn communicates with the gas passageway l2 through a valve orifice H3. The gas passageway 12 at its lower end communicates with the chamber 8 with the result that gas delivered by the conduit B passes through the valve body and is discharged at the vertical orifice ie where it is ignited, manually, and burns in a constant flame indicated at M.

The pilot light fuel control valve is indicated at D and comprises a relatively sharp needle [5 formed as an extension of an exteriorly threaded elongated plug it which is threadedly mounted for rotation in the upwardly extending interiorly threaded stud or boss ii on the upper face 9 of the valve body. This plug at its upper end is provided with a kerf it for the reception of a screw-driver or other suitable tool by means of which the plug and needle valve can be rotated to adjust the size of the valve orifice l3 and thereby control the amount of fuel delivery to the burner orifice it.

A flame cup or shield E surrounds the burner orifice l and has its bottom l9 clamped tightly against the valve body upper face 9 by a nut 29 rotatable upon the outer threaded portion of r the upwardly extending outlet and burner orifice Iii.

A secondary shield and cup is indicated at F and is clamped to the bottom of the valve body by the enlarged head 4 of the plug C.

The plugging or clogging up of the valve seat or orifice l3 by foreign matter is minimized and practically overcome by the use of a needle valve with a relatively sharp point and by the use of a needle valve which is positioned vertically in the gas passageway rather than horizontally.

To overcome corrosion, which heretofore has been'mentioned under the second cause for the clogging of the fuel control valve, the valve body :consequently corrosion is eliminated.

To overcome and minimize to the greatest degree the clogging of the fuel control valve by gums the valve is so located that it is maintained at a relatively high temperature. This minimizes the gum deposit. If the temperature of the gas is above the temperature at which the hydrocarbons are dropped from the gas as a deposit of gum the greater percentage of gum Wiil pass through the valve in the form of vapor. Our valve is kept hot and maintained at a relatively high temperature by the conduction of heat from the pilot flame M as it will be seen that the flame cup or shield E will be heated from the flame and due to its tight and rigid connection with the upper face of the valve body this heat from the cup will be conducted to the valve body. In the present construction the valve body is heated up to, as explained above, 250 to 300 degrees Fahrenheit depending upon its particular installation or arrangement in the stove or range, and we have found that by maintaining the valve body at this temperature approximately eighty percent of the gum ordinarily deposited in and upon the fuel control valves of pilot lights as heretofore constructed is eliminated. To state this simply, by heating the valve body and the valve eighty percent 'of the normal gum formation in and upon the valve is eliminated. 5

It will be evident that the large cup F also assists in protecting the valve body or fitting A and thereby assists in the maintenance of the valve body at the desired temperature.

The construction illustrated in the drawing and described is to be understood merely as illustrative of our discovery and inventive concept. It is to be realized that our improvedresults could be obtained by constructions which difier in detail from that illustrated and described.

Having disclosed the principle of operation of our improved construction and having made clear the manner in which the difficulties heretofore encountered in respect to pilot lights and the fuel control valves therefor can be overcome, what we desire to secure and protect to ourselves by Letters Patent is set forth in the following appended claims.

We claim:

1. An improved constant burning pilot light, comprising a body portion composed of aluminum having in its upper face a burner orifice at which is burned 'a vertically extending tongue of flame, a gas supply to said body, a gas passageway connecting said gas supply and said burner orifice, a horizontally disposed valve seat in said passageway, said body provided with an internally threaded and vertically upwardly extending boss that parallels in close relationship the flame burned at said burner orifice, a needle valve threaded and rotatably mounted in said threaded boss and provided with a sharp .pointed end of stainless steel cooperating with said horizontally disposed valve seat, and a flame shield surrounding said pilot light flame and having a side wall paralleling and closely adjacent to the boss carrying the needle valve, the parts operating to accomplish the purposes described.

2. An improved constant burning pilot light, comprising an aluminum body portion having a horizontally disposed upper face provided with a burner orifice at which a vertical tongue of flame is burned, a gas supply pipe connected to said body, a gas passageway in said body connecting the gas supply pipe and the burner orifice and provided with a horizontally disposed seat, an internally threaded boss above said seat and extending vertically from the body and paralleling the flame burnedat the burner orifice, a needle valve rotatably mounted in said boss and having a downwardly extending and vertically disposed lower end composed of stainless steel and terminating in a sharp point to form a needle cooperating with the aforementioned valve seat, and means for conducting the heat from the burner flame to the boss and the valve carried thereby for the purpose described.

3. A structure such as defined in claim 1,

wherein the entire pilot light including the body member, the flame shield and the boss are surrounded by a secondary flame shield.

ARTHUR STOCKSTROM. JOHN GERALD KOSKY. 

